KIDS today enjoy so much more out-of-school stimulation, than when children's telly lasted an hour, the “do not touch” signs outnumbered exhibits in museums, and only the best playgrounds had a see-saw, swings and a roundabout?

But from all around the world, evidence is mounting that even active custom-built playtimes are nowhere near as good for the young as that the pre-1970s generation invented every time a parent ordered: “Get from under my feet and play outside.” In fact, so many experts are raising concern at how little time children now spend exploring the woods, hillsides, streams and fields that were the main playgrounds of the past, there's even a name for it – Nature Deficiency Syndrome.

“It's ironic”, says Ruth Worsley, part of an Avon Wildlife Trust team that has launched a campaign to encourage parents, carers and children to make more use of natural spaces for play. “Adults think they are doing their best for children by giving them the latest gizmos, and keeping them safe from 'stranger danger' or injury, but the reality is that it's robbing young people of the chance to gain the skills and benefits that come from roaming around natural places, beyond the close watch of adults.

“Children need 'green' play to develop vital life skills for their own adulthood – skills, such as observing and analysing, assessing and avoiding risk, inventing and adapting, testing and learning their limits.” According to studies from Australia, Britain, Sweden, the United States, and elsewhere, it doesn't require a week up a mountain for children to get a healing 'green fix'; simply looking at nature helps them to become happier, healthier, calmer, perform better in school, solve problems, cope with stress and gain self-reliance.

Avon Wildlife Trust's response to the research includes introducing a new range of summer holiday activities at its Folly Farm and Willsbridge Mill wildlife education centres.

Every Tuesday, from next week to August 29, children aged eight to 12 can be dropped off at Folly Farm, Bishop Sutton, near Chew Valley Lake, for four hours of out-of-doors games, exploration and practical activities, including den-building, animal tracking, photography and making artwork from natural materials.

At Willsbridge Mill, in a peaceful South Gloucestershire valley on the outskirts of Bristol, there will be a different “Really Wild About...” event every Wednesday, from August 6 to 27, looking at bugs, ponds, rocks, fossils, and trees using hands-on games and equipment.

In addition, the trust is stepping up its work on greening school grounds, producing a free round-up of ideas for nature-based fun during the summer holidays.

On October 2, it will stage a Nature's Playground workshop for parents, carers and teachers.

The workshop will be run by Fiona Danks and Jo Schofield, co-authors of the much-praised Nature's Playground book (which Look at You featured in May) and will share practical ideas for helping children to connect with the natural world.

One group already taking advantage of the work is Tresa, a community association in south Bristol that recently won a £80,000 National Lottery grant to revamp a run- down park at School Road, Totterdown.

With advice from Avon Wildlife Trust, and ideas from local parents and pupils from the nearby Hillcrest Primary School, the group is designing the new-look park to offer a mix of built and natural play attractions, incorporating logs, stepping stones, rope, boulders and pebble mounds.

Group spokeswoman Alice Cabanas, the mother of two young boys, says: “Living in the inner city can cut children off from nature, and make them too dependent on adult-directed play.

“By using natural materials, creating places for wildlife and introducing structures that can be whatever the children want them to be, we're hoping to inspire an interest in the natural world, and give them a rewarding and creative space to play in.”

Ruth Worsley adds: “We know the world has changed since children had the freedom to go off alone in search of adventures. There are more dangers now, and we'd be very foolish to ignore them. But with our summer programme, tips, work with schools and Nature's Playground workshop, Avon Wildlife Trust hopes to show there are safe and easy ways to make nature a regular part of children's lives, that the benefits are real, and the experience will give children skills and interests that they will value for the rest of their lives.”